For the assignment

Task 1 - helm debug

1. This deployment is currently not working properly, can you figure out why?

We have no env for prefix, so we only have one prefix / for default and it call for "de" at the time And the svc name is now hello-world-en but the deployment and env are hello-world-de targetPort should be 8000 because container pod is listening on 8000

2. When querying different endpoints it should show each of the different services you created on the previous step:

• http://<address>/de should show "Hello Freund"
• http://<address>/es should show "Hello Amigo"
• http://<address>/fr should show "Hello Ami"

Write api to get "de", "es", "fr" in nodejs and use env "REGION" for helm deployment

app.get(`/${region}`, function(request, response) {
  response.send(`Hello ${world}`);
});

3. Deploy this applications to the istio service mesh

• 3.1 Expose this service to outside of the cluster by istio gateway ingress controller.

Using gateway and virtualservice to route /de; /es; /fr to the right region (deployment)

Example for de region:
  - name: "de"
    match:
    - uri:
        exact: "/de"
    route:
    - destination:
        host: hello-world
        subset: de

• 3.2 When query http://<address>/eu should load balancing round robind shows belows output "Hello Freund" "Hello Amigo" "Hello Ami"

Using destination rule trafficPolicy: Loadbalancer type (ROUND_ROBIN) for /eu (route around de/es/fr )

apiVersion: networking.istio.io/v1alpha3
kind: DestinationRule
metadata:
  name: hello-world-destination
spec:
  host: hello-world.default.svc.cluster.local
  trafficPolicy:
    loadBalancer:
      simple: ROUND_ROBIN
  subsets:
  - name: de
    labels:
      region: de
  - name: es
    labels:
      region: es
  - name: fr
    labels:
      region: fr

Task 2

• Implement a Python or Golang app /script to perform a periodically health-check for the cluster/apps i.e usage of the pods (CPU/MEM), status of pod/node,...etc without using kubectl if possible.

Using kubernetes client to grab the API, visual the output to python flask

*.py
#Get all pods from all namespace 
@app.route("/pods")
def display_pod():
    v1 = client.CoreV1Api()
    all_pods = v1.list_pod_for_all_namespaces()

#Get all containers information from all namespace
@app.route("/cont")
def display_cont():
    api = client.CustomObjectsApi()
    resource = api.list_namespaced_custom_object(group="metrics.k8s.io",version="v1beta1", namespace="", plural="pods")

*.html

#Showing pods information and status
    <tbody>
        {% for item in data %}
            <tr>
                <td>{{ item.status.pod_ip }}</td>
                <td>{{ item.metadata.namespace }}</td>
                <td>{{ item.metadata.name }}</td>
                <td>{{ item.status.phase }}</td>
            </tr>
    </tbody>

#Showing containers cpu/memory utilization
    <tbody>
        {% for pod in resource %}
        {% set containers = pod['containers'] %}
        {%for container in containers %}
            <tr>
                <td>{{ pod.metadata.name }}</td>
                <td>{{ container['usage']['cpu'] }}</td>
                <td>{{ container['usage']['memory'] }}</td>
            </tr>
        {% endfor %}
    </tbody>